Question

Epithelial tissue is-
A) Protective covering
B) Reproductive structure
C) Nerve cells
D) Corpuscles

Answer 1

Epithelial tissues line the cavities and surfaces throughout the body, on the inside as well as on the outside.

Complete Answer:
Epithelium is a basic type of animal tissue. It is a continuous, thin protective layer of cells. Throughout the body, epithelial tissues line the outer surfaces of organs and blood vessels, also lines the inner surfaces of cavities of various internal organs. Epidermis is a common example, it is the outermost layer of the skin.
There are three types of epithelial cells- squamous, columnar, and cuboidal. These can be arranged in a single layer of cells composed of either squamous, columnar, or cuboidal and is called a simple epithelium. It can be present in two or more stratified layers which can be compound or either squamous, columnar or cuboidal. A layer of columnar cells can be observed as stratified due to the placement of the nuclei in some tissues. Such a kind of tissue is called pseudostratified. All glands are composed of epithelial cells. Epithelial cells have secretion, absorption, protection, transcellular transport, and sensing as their functions.
There are no blood vessels in the epithelial layer, they receive nourishment through diffusion of substances through the basement membrane from the connective tissue underlying it. There are well employed cell junctions in epithelial tissues.


Thus, the correct answer is- A. protective covering.

Note: The epithelial tissue forms the epithelium of various organs and cavities of the body. The skin is also made up of epithelial cells. It is considered an important barrier of innate immunity.